This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This study is a single-blinded, placebo-controlled trial to determine the effects of DIM supplementation in patients with systemic lupus erythmematosus. A total of 30 individuals will be enrolled into this 14-month study. Ten patients will receive placebo, 10 will receive study drug at a daily dose of 300 mg, and 10 will receive study drug at a daily dose of 600 mg. Dosing will span 52 weeks. Drug or comparably packaged placebo will be administered orally with meals twice per day. Study subjects will be randomly assigned to one of the three treatment groups. The randomization schedule will be set up by the Bio-Statistics unit. The Investigator will call the Bio-Statistics unit once the subject signs the Informed Consent Form in order to learn which treatment regimen the subject is assigned to. Patients and control subjects will be given the appropriate amount of study medication at each visit to take home with them. Study personnel will monitor compliance by asking the patient to return any unused study medication at each visit for drug accountability. In addition, medication logs will be kept by the study subject and will be presented to the study coordinator at each visit. The subject, but not study personnel, will be blinded to the study drug assignments.